Process of recovering wool-fat.



" UNITED STATES Patented May 31, 1904.

PATENT ()FFICE.

CHARLES E. SWVETT, OF PROVIDENCE, RHODE ISLAND, ASSIGNOR OF ONE- HALFTOROBERT H. HUTCHISON, NEWV YORK, N. Y.

PROCESS 0s RECOVEBING WOOL-FAT.

SPECIFICATION forming part of Letters Patent No. 761,265, dated May 31,1904. Application filed March 1 0, 1908. Serial No. 147,174. (Nospecimens.)

To all whom it may concern:

Be it known that 1, CHARLES E. SWETT, a citizen of the United States,residing at Providence,- in the county of Providence and State of RhodeIsland, have invented a new and useful Process of Extracting Fat fromWool Wash-Waters, of which the following is a specification.

This invention relates to a novel process for the recovery of the fatsfrom wool wash-water.

It may be stated by way of premise that wool-fleece is usually cleansedby washing with alkalies dissolved in water. The washwater sometimes hassoap added to it, sometimes not. By this means an organic excretionknown as suint, together with various substances generically known asdirt, is removed. This suint contains elements of recognized valueforinstance, woolwax, which is a highly-complex body, potash salts, and ifsoap has been added to the wash-waters this soap will also be containedin said suint. The article of chief value in said suint is the fat. Allfats are valuable; but the value of wool-fat as ordinarily recovered islessened by its dark color and objectionable odor,

which damaging characteristics appear to be due chiefly to a process ofputrefaction which is incidental to the recovery of the fat by usualmethods.

The object of my invention is twofold: first, the recovery of the fat ina more merchantable condition than by usual methods, and, second, themore complete removal of fat and accompanying organic matters from thewater than by usual methods. In the suint the fats exist partly as soapand partly in emulsion. It has been proposed to first add anacid to thisfatty emulsion or suint, and thereby liberate the fat y matters from theemulsion; but this has been found to be impracticable, for the reasonthat if the greasy wash-waters be so treated the fats will remainsuspended in a finely-divided condition in the liquid, neither rising tothe surface nor falling to the bottom. To overcome this difficulty, thewater is sometimes heated to a relatively high temperature; but thistreatment is unduly expensive. The more usual method is to allow thewash-waters to putrefy, after which by the addition of an acid a more orless satisfactory separation is efiected. Obviously, however, by thismethod the generation of noxious odors is in- .cidental andthe fatafterward separated is lessened in value by its. dark color andobjectionable odor.

To the accomplishment of the objects hereinbefore stated, the processoriginated by me as distinguished from those above recited is practicedin the following manner: To the fresh cool greasy water an oxidizingagent, preferably an alkaline manganate or permanganate, is added. If analkaline manganate or permanganate be used, the further addition isstopped when the color imparted to the water by such addition disappearsrather slowly from the solution. I next add an alkali-neutralizing agentor acid until the fat in dilute solution and emulsion is separated andrises to the surface of the water as a thick magma. This magma is thenremoved, and the grease is separated therefrom in any approved manner,as by the expression of the free moisture in a press or by removing thegreater portion of the Water by mechanical means and recovering thegrease from the resulting mass by the action of avolatile solventsuchas, for instance, carbon disulfid or petroleum-naphtha, thepetroleum-naphtha being generally preferable.

By the practice of this method a wool-fat of good merchantable color andpractically odorless is secured. No objectionable odors are incidentalto such recovery, and as the abstraction of the organic matter iseffective the pollution of the water-course into which effluent wastewater escapes is avoided. It should be understood, however, that whilethe process is preferably practiced in the particular manner recited Ido not limit myself to this exact order of procedure, since it ispossible to vary the same somewhatas, for instance, to treat theemulsion first with acid and thereafter with an oxidizing agentwithoutdeparting from the spirit of the invention.

What I claim is 1. That process for the recovery of Woolfat from WOOlWash-Waters Which consists in adding to the Water an alkaline manganateor permanganate until the color imparted to the Water by such additiondisappears from the solution, next adding an acid until the fat indilute solution and emulsion is separated and rises to the surface ofthe Water as a thick magma, and thereafter abstracting the fat from themagma thus produced.

2. That process for the recovery of WOOlfat from Wool Wash-water whichconsists in

